1. Field of the Invention
The present invention relates to an Integrated Circuit (IC) assembly having a routing structure mounted on a Printed Circuit Board (PCB), and more particularly to an IC assembly which can simplify the routing path on the PCB by using an IC mounted on a PCB.
2. Description of the Related Art
In general, Integrated Circuits (ICs) are fixed to a Printed Circuit Board (PCB) used in electronic appliances. On a PCB, ICs are connected to each other through conductive lines extending between pins and pads, etc.
The IC includes layered circuits including simple layers, cells, cell blocks, etc. Each layer includes a variety of circuit devices such as transistors, resistors and capacitors, each of which performs a specific function.
Each layer of the IC includes a plurality of circuit blocks or groups. In order to distribute power and signals between the inside and the outside of the IC, the IC uses conductors of multiple levels which distribute the power and signals between the layers.
As shown in FIG. 1, ICs 2 are connected to each other through a serial or parallel path on a PCB 1. The ICs may be laid out at a location either near to or far from a central portion of the PCB 1. Further, a power source/reference clock 3 necessary for each IC is connected to the IC through an individual routing path from a battery or power source.
When the routing paths extend over relatively long distances for connecting devices, the paths may cause coupling noise or cross-talk, which in turn causes leakage of current, thereby resulting in a bad influence on the transmission of signals.
Due to recent developments to increase processing speed, capacitor devices on the PCB may cause coupling between different signal lines of the same layer or between signal lines of different layers or may even cause short-circuiting between the signals lines.
Further, the routing may be limited in order to form a power-plane or for a necessary grounding.
The current trend is that a great number of ICs are used in addition to the existing modem and RF unit as hardware for a mobile phone, and inter-chip (chip-chip) routing is increasing in the mobile phone. Such additionally used IC devices include, for example, an application processor, a 3D-chip multimedia memory Wireless Local Area Network(WLAN), Bluetooth solution(BT)solution, digital multimedia broadcasting (DMB) solution, etc. In order to allow the increasing routing, the number of layers may be increased and the routing density may also increase. However, such an increase inevitably causes an increase in the manufacturing cost of the product, and an increase of the coupling noise between layers.